Answer:
The answer to your question is A. decreases and basicity decreases.
Explanation:
0.1 M HCl is an acid solution that means that its pH is between 0 and 6.9.
0.1 M KOH is a base that means that its pH is between 7.1 and 14.
If we add HCl to NaOH the pH of NaOH will start to decrease and the basicity will also decrease.
